Code Map feature was working fine in Visual Studio 15 - Preview 3. but after installation of Preview 4, Code Map option is disappeared. (Initially I have installed Workload - .NET desktop development)
After little search, I found in Release notes that, Architecture Diagrams and Analysis Tools require other workloads to be installed. So I added suggested workloads - Web Development, Windows desktop development with C++
but even after adding these components, I am unable to create/open existing code maps.